Even though the Tesla Model S has retained its same basic shape since it went on sale in 2012, what's going on under the hood has been anything but stagnant.

The automaker's over-the-air updates for the electric car have put the old guard on notice: People expect their cars to act like the computers and phones sitting on their desks and in their pockets. That means updates and new features—constantly.

Mostly, Tesla has done that. With the major exception of a hardware changeover in early 2017, Tesla owners have had new features unlocked or refined, new interfaces implemented, and safety improvements come to their cars—sometimes without setting foot in a service center.

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That's because all owners of a Tesla Model S car get those software upgrades automatically, over the air, for free. Try doing that with your new wiper-blade defroster.

Virtually every aspect of Model S operation, from the climate control system to the suspension, is controlled by software. "A computer on wheels," some have called it.

That software, of course, can be updated. The Model S is unique among cars in that it can be reprogrammed remotely from the factory over its 3G or wi-fi network. Since the Model S first hit the streets in June 2012, there have been a number of major software updates—on average, one every few months.

2014 Tesla Model S in China

2014 Tesla Model S in China

[EDITOR'S NOTE: This article was first published in June 2014; we have now updated it to reflect additional Model S software updates from that date through May 2018. The new material is at the end of the article.]

As a Model S owner, I can testify that the cumulative effect has been to significantly improve the car.

I've come to look forward to those mornings where I'm greeted by a surprise message on the 17-inch touch screen: A new software update is available; would I like to download it now, or schedule it for later?

To download the new software, the Model S must be in "Park" for about two hours, so I typically agree to the car's default suggestion of a download at 2 am the next morning.

First new features

The software update program kicked off in October 2012, after just a few hundred Model S cars had been built.

Unfortunately, it's difficult to pin down the precise timing of many of the various software updates.

ALSO SEE: Life With Tesla Model S: One Year And 15,000 Miles Later

There were often long lags between the time when the first and last cars in the fleet were updated. Many sub-versions were issued that had only trivial changes from previous versions—and not all versions were sent to all cars.

2014 Tesla Model S

2014 Tesla Model S

Here, then, is a rough chronology, with approximate dates, of the various Model S software upgrades over the past two years:

After explaining how the over-the-air software update process worked, that first October 2012 update (actually three separate updates dated the same day) introduced several new features. Among them:

*Supercharging. The first Superchargers were set to open two months later; the update enabled the on-board Supercharging software.

*Driver profile. Different drivers could now store into memory their preferences for seat, mirror, and steering-wheel positions, along with preferred settings for lights, locks, maps, and display formats.

*Creep Mode. This new feature mimicked the slight forward motion of a standard car when idling, and could be toggled on or off by drivers.

*Lower Rated Range. Based on a newer, tougher EPA range standard, the new algorithm reduced the typical full-charge "rated range" readout from 300 miles to 265 miles. The new "rated range" was simply more realistic, although the actual range of the car remained unchanged.

Other minor updates included a quicker "wake-up" on entry and various improvements to the GPS map.

A couple of months later, with production finally starting to ramp up in earnest, software update 4.0 introduced a bundle of new features. Among them:

*More aggressive throttle response. Which just added to the car's embarrassment of riches, in terms of sheer performance.

*Voice Command for Audio, Navigation, and Phone

*Sleep Mode. To reduce the power drain from the battery, computers and displays would be powered down when the car was off.

Additional tweaks made it possible to control the fan or sunroof via the thumb-wheel on the steering wheel; make calls from the GPS map, and access music from a USB drive.

2015 Tesla Model S 70D in new Ocean Blue color

2015 Tesla Model S 70D in new Ocean Blue color

Also, for the first time, the release notes for the updated software version became available on the car's touchscreen, by tapping the "T" logo at the top of the screen.

My 2013 Tesla Model S was delivered in February of that year, so it came from the factory with version 4.0 installed.

Missing, however, was the sleep-mode feature; it had apparently proved so troublesome and bug-ridden that it had been disabled fleet-wide.

Scheduled charging

My first update, Version 4.3, allowed owners to set a specific time for their vehicle to start charging. The idea was to take advantage of some utilities' cheaper overnight rates.

ALSO SEE: Why Tesla's Elon Musk Must Sell 6 Million Electric Cars To Make History

Unfortunately, my utility company offers no such time-of-day rate structure, so I've never used the delayed-charge feature. For some owners, though, scheduled charging has been a big money-saver.

Version 4.5, introduced in summer 2013, had a slew of new features. Among them:

*Supercharger Locations Displayed on GPS Map. But as I discovered, without the Tech package and its GPS route-instruction feature, the distance to the Supercharger shown on the display turned out to be a straight line between the two points as-the-crow-flies, not the actual road mileage. Pretty useless.

*Flexible Charging Limits. Originally, the Model S had only two charge modes: Standard (90-percent charge) and Max Range (100 percent). With update 4.5, owners could now set whatever charging limit they wanted.

2012 Tesla Model S

2012 Tesla Model S

So what charge limit did I choose as my default setting? I wanted to keep it as high as possible without compromising battery longevity.

Tesla wouldn't give me a recommended number for maximum battery life. So I looked to my Chevy Volt, which has extremely conservative charge and discharge limits in the name of battery longevity. A "full" charge on the Volt is only about 80 percent, so I settled on that number as my default charging limit for the Model S.

In addition, update 4.5 made improvement to map fonts, defrost functions, battery heating, and the phone contact list.

Waiting for sleep mode

Having calculated that I lost about 4.5 kilowatt-hours each day of "vampire" power when the car was parked—equivalent to 5,000 miles of driving per year—I was eagerly awaiting an improved sleep mode.

In a forum in Oslo, Elon Musk had promised a software update that would virtually wipe out vampire losses by mid-summer of 2013.

Sadly, it was not to be.

I finally received version 5.8 with the alleged vampire-killer update in November 2013.

Although a big improvement, I found I was still losing about 1 kwh per day, and that continues to this day. (No other electric car that I'm aware of has vampire losses—of any sort.)

2015 Tesla Model S 70D in new Ocean Blue color

2015 Tesla Model S 70D in new Ocean Blue color

Various people at Tesla have told me a final Sleep Mode software solution is on the way. But after more than a year of waiting, I'll believe it when I see it.

Version 5.8 had a number of other updates. Among them:

*The addition of wi-fi as an alternative data-connection method. Once a WiFi network had been selected, the car would auto-connect whenever it came within range.

*Heading-Up display mode on the GPS.  For those who like the map to match the view out the window. Other minor map improvements were included.

*Tow Mode. To be towed, the Model S must be in neutral with the parking brake off. Some owners were unaware of this, and trouble sometimes resulted. Now, one simple button touch assures both owner and tow-truck driver that the car is safe to tow.

*Improved Creep Mode. Since the time my car was new, I'd noticed an occasional annoying jerkiness to the creep mode. Now that's gone.

2012 Tesla Model S

2012 Tesla Model S

Other changes included a screen-cleaning mode, improvements to radio presets, driver profiles, rated range, and display brightness.

The most recent software version, 5.9, had more noticeable improvements:

*Hill-start assist.  When starting on a hill, the Model S now automatically brakes to hold its position until the driver's foot touches the accelerator pedal. It works great.

*Improved Air Suspension.  The "Low" position, after being disabled in the wake of two battery fires caused by underbody strikes of highway debris, was restored.  And now, instead of lowering automatically above a speed of 60 mph, the suspension can be set to lower at any speed. (Even 0 mph, for the lowriders in the crowd.)

In addition, the "High" and "Very High" positions can be maintained at higher speeds than before.

There are also a number of minor refinements that don't merit a complete explanation here—although one man's "minor" can be another's "huge deal."

MORE: Tesla Annual Meeting: What We Learned That Was New

One example: For most people, a slightly larger font on the time, date, and temperature readouts on the instrument panel is hardly a stop-the-presses development.

But for me, cursed with aging eyes and crappy glasses, it's a game-changer. Several times each day, I give thanks to CEO Elon Musk for the larger font.

September 2014: Version 6.0 is released

Unfortunately, the main feature of release 6.0—traffic-based navigation—didn’t apply to me because I don’t have GPS navigation. I have a map that shows my current location, which can pinpoint the location of any address.

But back in 2012, when I configured my car, turn-by-turn navigation guidance was part of an optional $4,000 tech package, which I chose to forego.

A couple of other features of 6.0 were also useless for me. I don’t keep a calendar on my smartphone, so the Bluetooth calendar sync was irrelevant.

And the ability to enter your car’s nickname into its computer system, much touted by Musk, seemed trivial and silly.

2015 Tesla Model S 70D in new Ocean Blue color

2015 Tesla Model S 70D in new Ocean Blue color

I did find the location-based air suspension feature of 6.0 to be quite handy, however. I'm tall and creaky, and I have a tough time getting in and out of the low-slung Model S.

Raising the air suspension to Very High makes the task a bit easier. Now the car automatically rises to Very High every time I pull into my driveway, allowing me to exit (and later re-enter) with comparative alacrity.

(Hey, Elon, how about a tall-guy option to automatically raise the suspension every time the car is put into Park?)

2015 Tesla Model S 70D, Apr 2015 [photo: David Noland]

2015 Tesla Model S 70D, Apr 2015 [photo: David Noland]

Version 6.1 (January 2015)

I missed most of the benefits of Version 6.1 as well.

The big new items were the first steps toward full autopilot capability: traffic-aware cruise control and forward collision warning. There’s also an auto-dimming function for the headlights.

Those updates, however, applied only to cars built since mid-2014 with autopilot hardware (cameras, radar, and ultrasonic sensors).

I got a taste of both of these features on a service loaner car a few months back, and they both seem to work very well.

Without navigation, I also missed out on the trip energy predictor, which sounds like a great feature for drivers like me who do a lot of long-distance Supercharger-to-Supercharger driving.

But I did appreciate three features of 6.1:

  • steering guidelines in the back-up camera
  • the option for a display of battery percentage charge remaining, rather than just rated range. I’ve long been puzzled by the Tesla’s lack of such a display, a no-brainer standard feature on all other electric cars.
  • the projected range display now defaults to the “Average” setting, a big improvement over the entirely useless “Instantaneous” setting. In the future, this will save me uncounted annoying screen taps.

2015 Tesla Model S 70D, Apr 2015 [photo: David Noland]

2015 Tesla Model S 70D, Apr 2015 [photo: David Noland]

Spring 2015: Update 6.2

The most recent major update, 6.2, was hyped as “The End of Range Anxiety"—though, sadly, that didn’t mean a battery range increase to 500 miles.

Instead, new software monitors battery charge, real-time location, and the presence of nearby charging stations. If you’re in danger of going beyond the range in which you can reach a charger, the system will alert the driver.

The trip-energy predictor was also upgraded to take into account temperature, wind, and elevation changes. And the Autopilot took a further step forward, with automatic emergency braking and blind-spot warning.

Unfortunately, lacking navigation and the Autopilot hardware, I got none of these improvements. 

2015 Tesla Model S 70D in new Ocean Blue color

2015 Tesla Model S 70D in new Ocean Blue color

However, I sampled the blind-spot warning function on a service loaner Model S, and found it disappointing. I’d hoped for a warning light in the driver's-door mirror—the obvious places for it.

But instead, the light is on the dashboard—the last place you’re going to be looking just before you change lanes. 

If you actually begin to swerve into a car in your blind spot, inadvertently, the sonar triggers an audible beep. That’s all well and good, but there should be a much better and more obvious early warning of that car’s presence.

The one feature of 6.2 my car can use is Valet Mode, which limits top speed to about 70 mph and drastically reduces the available power. Haven’t used it yet, however.

2013 Tesla Model S - valet mode provided by Rev 62 [photo: David Noland]

2013 Tesla Model S - valet mode provided by Rev 62 [photo: David Noland]

The most recent tweak to 6.2, installed at my last service visit, includes map listings of the 20 kw-destination chargers that Tesla is rapidly deploying at hundreds of hotels and inns around the country.

Version 7.0 (October 2015)

This update improved the functionality of Autopilot, including Autosteer, Autopark, automatic lane changes, and blind-spot monitors.

It required the Hardware 1 (at least) package for drivers to enable the features.

Version 7.1 (January 2016)

Autopilot was updated to include perpendicular Autopark and "Summon," a new feature that could reverse the car without a driver for tight parking spots.

Autopilot was incrementally improved for Hardware 1 owners, although upcoming Hardware 2 owners wouldn't see the same functionality for more than a year later.

Version 8.0 (September 2017)

With Version 8.0, Tesla took longer strides to improve its hardware and user control.

For starters, the media player and maps were dramatically improved in the user interface. Voice commands were updated to include more natural search terms, and to make location searches easier.

Tesla improved regenerative braking for some models, and for Model X owners, the falcon doors were sped up to open and close faster.

Version 8.1 (March 2017)

In spring, the latest update improved Hardware 2 cars to include more Autopilot features including Autosteer up to 90 mph, adaptive cruise control, blind-spot monitors, automatic emergency braking, auto lane change, Autopark and Summon, automatic high beams, and speed assist.

The comprehensive update applied to all cars made after February 2016, but some features wouldn't be activated unless owners purchased the associated extra-cost packages (Autopilot and/or Fully Self Driving).

Small update (February 2018)

Roadside assistance can be contacted now through the "T" control screen.

Small update (March 2018)

Owners can now rearrange the touchscreen icons for their own use and can unlock their doors through a nearby, paired smartphone. 

Automatic emergency braking speeds were increased to up to 90 mph.

Small update (April 2018)

Autopilot speed adjustment was moved to the right scroll wheel on the steering wheel.

Some Model 3 vehicles also received automatic high beams.

Aaron Cole also contributed to this report.